The present invention relates generally to a liquid dispenser, and more particularly to apparatus for dispensing a preselected amount of liquid from bellows.
While apparatus for dispensing a liquid are well known in the dispenser art, relatively few store the liquid (prior to dispensing) in a bellows. Various reasons may be postulated for this. First, a bellows configuration is difficult to grasp and hold, let alone manually compress axially to collapse the bellows. Second, the amount of liquid discharged from the bellows varies with the degree of axial compression of the opposed bellows ends so that a uniform expression or expulsion of liquid is not easily obtainable. For these and other reasons, the use of bellows in a liquid dispenser is not common. Therefore, the need remains for a liquid dispenser which stores the liquid (prior to dispensing) in a bellows and overcomes the various disadvantages associated with conventional bellows-type dispensers.
Accordingly, it is an object of the present invention to provide apparatus for dispensing a preselected amount or dosage of liquid where the liquid is stored in at least one bellows.
Another object is to provide such apparatus which in one embodiment dispenses in turn multiple dosages of liquid.
A further object is to provide such apparatus which in one embodiment dispenses a generally reproducible preselected amount or dosage of liquid.
It is another object to provide such an apparatus which is simple and economical to manufacture, use and maintain.
It has now been found that the above and related objects of the present invention are obtained in apparatus for dispensing a preselected amount of liquid comprising a base; at least one bellows at least partially disposed in the base, and a manually actuatable actuator in telescopic relationship with the base for compressing the bellows therebetween. The bellows is configured and dimensioned to hold a first preselected amount of liquid, and the actuator discharges a second preselected amount of liquid from the bellows.
In a preferred embodiment, the bellows is initially provided with a seal to preclude release of liquid therefrom, and the actuator includes means for rupturing the seal to enable liquid discharge from the bellows. After rupture of the seal, all portions of the seal preferably remain secured to the bellows. The rupturing means typically effects a piercing action on the seal.
The actuator may define a cup-shaped portion configured and dimensioned to receive and maintain liquid dispensed from the bellows and optionally a hollow center post portion having one end in fluid communication with the bellows after rupture of the seal and an opposite end projecting upwardly from the cup-shaped portion.
In another preferred embodiment, the at least one bellows is a plurality of integrally joined bellows in fluid communication with one another and at least partially disposed in the base. The actuator is capable of sequentially assuming multiple orientations relative to the base, thereby to sequentially dispense multiple doses of liquid form the bellows. The multiple orientations are multiple differing telescopic orientations. The base and the actuator preferably bear visible indicia indicating the relative rotational orientation of the base and the actuator.
In a further embodiment, the base is in non-rotational sliding telescopic engagement with the actuator due to an internal key and keyway assembly such that axial movement of the actuator relative to the base in a given direction effects at least partial collapse of the bellows. The base and the actuator preferably bear visible indicia indicating the relative orientation of the key and keyway.
The bellows is preferably disposed intermediate a lower-facing surface of the actuator and an upper-facing surface of the base. The first and second preselected amounts of liquid are preferably substantially the same, although they may be appreciably different.